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The co-elution, pervasive isomers, and frequently occurring in-source fragmentation definitely hinder the comprehensive characterization of the multiple components from traditional Chinese medicine (TCM) by liquid chromatography/mass spectrometry. Herein, a dimension-enhanced strategy, by utilizing an ion mobility quadrupole time-of-flight mass spectrometer coupled to ultra-high performance liquid chromatography (UHPLC/IM-QTOF-MS) with the ability of offering four-dimensional information (retention time, Rt; drift time or collision cross section, CCS; accurate mass of precursors; and accurate MS2 product ions), is presented. Shuanghe Decoction (SHD) is a classic tonifying formula composed of nine herbs, however, little is known to its chemical complexity, hitherto. Good chromatographic separation was achieved on an HSS T3 column, and by the Vion™ IMS-QTOF high-resolution mass spectrometer, data-independent MSE and High-Definition MSE (HDMSE) in both the negative and positive electrospray ionization modes were employed for acquiring the collision-induced dissociation-MS2 data. A self-built database, including 642 known compounds, was established, which assisted to perform the automated peak annotation by UNIFI™. By reference to 55 compounds, totally 236 components were identified or tentatively characterized from SHD with 4D data recorded. The combination of negative and positive modes could yield more information complementary to structural elucidation. Compared with the conventional MSE, HDMSE exhibit of merits in the provision of CCS, better separation and detection those easily co-eluting components, and reduction of the false positives in the identification results. Conclusively, the combination of HDMSE acquisition, in-house library, and UNIFI-facilitated automated peak annotation, renders a potent approach dedicated to deconvoluting the chemical composition of complex systems like TCM formulae.

Rationale: Kaixin San (KXS) is a prescription traditional Chinese medicine (TCM) with the effects of "tonifying the kidney and brain" and "improving memory". The volatile organic compounds (VOCs) in KXS could effectively improve senile dementia and depression, but only few studies have focused on the overall characterization of VOCs in KXS and the quantitative study of the main active components. Methods: We have developed a strategy to correlate the results from headspace gas chromatography/ion mobility spectrometry (HS-GC/IMS) and headspace gas chromatography/mass spectrometry (HS-GC/MS) for the comprehensive characterization of VOCs in KXS and the quantitative analysis of the main pharmacodynamic substances. Results: A totsal of 68 low molecular weight VOCs were identified in KXS by HSGC/IMS at room temperature and atmospheric pressure; 117 VOCs were identified and 10 components (isocalamenediol, α-asarone, β-asarone, methyl eugenol, isoeugenol methyl ether, camphor, anethol, 2,4-di-tert-butylphol, linalool, asarylaldehyde) as the quality markers of KXS based on HS-GC/MS. Conclusions: This results from this study provide a foundation for quality control, pharmacodynamic mechanism research and further development of KXS, and provides more convincing data supporting the VOCs of other natural products. [ABSTRACT FROM AUTHOR]

Zingiberaceae plants are distributed in the tropical and subtropical regions of the world, being used in many famous medicinal materials. Meanwhile, some Zingiberaceae plants are important horticultural flowers because they are green all year round and have special aromas. To conduct an extensive investigation of the resources of Zingiberaceae plants, the volatile compounds of ten species of Zingiberaceae were extracted and analyzed by GC–MS, including Costus comosus var. bakeri (K.Schum.) Maas, Curcuma rubescens Roxb., Curcuma aeruginosa Roxb., Curcuma attenuata Wall., Hongfengshou, Hedychium coronarium Koeng, Zingiber zerumbet (L.) Smith, Hedychium brevicaule D. Fang, Alpinia oxyphylla Miq., and Alpinia pumila Hook.F. A total of 162 compounds were identified, and most of those identified were monoterpenes and sesquiterpenes. (E)-labda-8(17),12-diene-15,16-dial, n-hexadecanoic acid, 4-methoxy-6-phenethyl-2H-pyran-2-one, and L-β-pinene were found in high concentrations among the plants. These ten species of Zingiberaceae contained some of the same volatiles, but their contents were different. Pharmacological effects may be associated with the diversity of volatiles in these ten plants.

Asatone and isoasatone A from Asarum ichangense Cheng were determined to be defensive compounds to some insects in a previous investigation. However, the anti-insect activity mechanisms to caterpillar are still unclear. The compounds asatone and isoasatone A from A. ichangense were induced by Spodoptera litura. The anti-insect activity of asatone and isoasatone A to S. litura was further tested by weight growth rate of the insect through a diet experiment. Isoasatone A showed a more significant inhibitory effect on S. litura than asatone on the second day. The concentration of asatone was higher than isoasatone A in the second instar larvae of S. litura after 12 h on the feeding test diet. Both compounds caused mid-gut structural deformation and tissue decay as determined by mid-gut histopathology of S. litura. Furthermore, some detoxification enzyme activity were measured by relative expression levels of genes using a qPCR detecting system. Asatone inhibited the gene expression of the cytochrome P450 monooxygenases (P450s) CYP6AB14. Isoasatone A inhibited the relative expression levels of CYP321B1, CYP321A7, CYP6B47, CYP6AB14, and CYP9A39. Asatone increased the relative gene expression of the glutathione transferases (GSTs) SIGSTe1 and SIGSTo1, in contrast, isoasatone A decreased the relative gene expression of SIGSTe1 by about 33 fold. Neither compound showed an effect on acetylcholinesterase SIAce1 and SIAce2. The mechanism of anti-insect activity by both compounds could be explained by the inhibition of enzymes P450s and GSTs. The results provide new insights into the function of unique secondary metabolites asatone and isoasatone A in genus Asarum, and a new understanding of why A. ichangense is largely free of insect pests.